Merge remote-tracking branch 'benpeart/fscache-per-thread-gfw'

This brings substantial wins in performance because the FSCache is now
per-thread, being merged to the primary thread only at the end, so we do
not have to lock (except while merging).

Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>

builtin/add.c

@@ -461,7 +461,7 @@ int cmd_add(int argc, const char **argv, const char *prefix)
 	die_in_unpopulated_submodule(&the_index, prefix);
 	die_path_inside_submodule(&the_index, &pathspec);
 
-	enable_fscache(1);
+	enable_fscache(0);
 	/* We do not really re-read the index but update the up-to-date flags */
 	preload_index(&the_index, &pathspec, 0);
 

builtin/checkout.c

@@ -414,7 +414,7 @@ static int checkout_paths(const struct checkout_opts *opts,
 	state.istate = &the_index;
 
 	enable_delayed_checkout(&state);
-	enable_fscache(1);
+	enable_fscache(active_nr);
 	for (pos = 0; pos < active_nr; pos++) {
 		struct cache_entry *ce = active_cache[pos];
 		if (ce->ce_flags & CE_MATCHED) {
@@ -434,7 +434,7 @@ static int checkout_paths(const struct checkout_opts *opts,
 			pos = skip_same_name(ce, pos) - 1;
 		}
 	}
-	enable_fscache(0);
+	disable_fscache();
 	remove_marked_cache_entries(&the_index, 1);
 	remove_scheduled_dirs();
 	errs |= finish_delayed_checkout(&state, &nr_checkouts);

builtin/commit.c

@@ -1364,7 +1364,7 @@ int cmd_status(int argc, const char **argv, const char *prefix)
 		       PATHSPEC_PREFER_FULL,
 		       prefix, argv);
 
-	enable_fscache(1);
+	enable_fscache(0);
 	if (status_format != STATUS_FORMAT_PORCELAIN &&
 	    status_format != STATUS_FORMAT_PORCELAIN_V2)
 		progress_flag = REFRESH_PROGRESS;
@@ -1405,7 +1405,7 @@ int cmd_status(int argc, const char **argv, const char *prefix)
 	wt_status_print(&s);
 	wt_status_collect_free_buffers(&s);
 
-	enable_fscache(0);
+	disable_fscache();
 	return 0;
 }